Avalanche Forecast
Regions: Boundary, East Stikine, Kispiox, Ningunsaw, Northwest Coastal, Northwest Inland, Stewart, West Stikine.
Avoid large, steep and open slopes at higher elevations where persistent weak layers are more likely to be triggered.
Confidence
Moderate
Avalanche Summary
No significant avalanche activity has been reported since Friday.
Last week, human-triggered persistent slab avalanches were reported to size 3, in alpine features. These failed 20 to 40 cm deep, likely on the surface hoar buried in early March.
Snowpack Summary
Southerly winds have redistributed recent snowfall into deep pockets on north facing slopes. Winds are forecast to shift west/northwest on Monday, likely creating loading on all aspects.
Two layers of concern currently exist in the upper-mid snowpack. Surface hoar on a crust can be found 20 to 80 cm deep. This layer has been reactive where a slab has consolidated above. And a layer of facets, surface hoar and/or a crust from mid-February is buried 50 to 100 cm deep. This layer produced large natural and human-triggered avalanches last week.
The remainder of the snowpack is well consolidated with no current concerns.
Weather Summary
Sunday Night
Cloudy with flurries. 20 to 30 km/h southwest ridgetop wind. Treeline temperatures drop to -10 °C.
Monday
A mix of sun and cloud. 25 to 35 km/h west ridgetop wind. Treeline temperature -7 °C.
Tuesday
Cloudy with up to 5 cm of snow. 30 to 50 km/h southwest ridgetop wind. Treeline temperature -4 °C.
Wednesday
Cloudy with up to 10 cm of snow. 50 to 70 km/h southwest ridgetop wind. Treeline temperature -2 °C as freezing levels rise to 1200 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avoid shallow snowpack areas, rocky outcrops, and steep terrain where triggering is most likely.
- Be alert to conditions that change with elevation, aspect, and exposure to wind.
- Be aware of the potential for large avalanches due to buried weak layers.
Avalanche Problems
Persistent Slabs
Layers of facets and surface hoar have shown recent reactivity. Choose small, low angle slopes as uncertainty exists.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1.5 - 3
Wind Slabs
Variable winds have likely redistributed recent snow into lee terrain features on many aspects. Wind slabs will be most reactive where they overlay a buried surface hoar layer. Expect locally variable wind effects.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 1.5